Environmental Technology Verification
Baghouse Filtration Products
W. L. Gore & Associates, Inc.
5117 High Durability PPS Laminate Filtration Media
(Tested March - April 2012)
Prepared by
RTI International ETS Incorporated
HRTI
INTERNATIONAL
Under a Cooperative Agreement with
U.S. Environmental Protection Agency
EPA
ETV?
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Environmental Technology Verification
Report
Baghouse Filtration Products
W. L. Gore & Associates, Inc.
5117 High Durability PPS Laminate Filtration Media
(Tested March - April 2012)
Prepared by
RTI International
ETS Incorporated
EPA Cooperative Agreement CR 83416901-0
EPA Project Officer
Michael Kosusko
Air Pollution Prevention and Control Division
National Risk Management Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
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THE ENVIRONMENTAL TECHNOLOGY VERIFICATION
PROGRAM
ET/
SEPA
U. S. Er.i,-in>r±i3Lt3l Protection Assicy
HRTI
INTERNATIONAL
ETV JOINT VERIFICATION STATEMENT
TECHNOLOGY TYPE:
APPLICATION:
TECHNOLOGY NAME:
COMPANY:
ADDRESS:
WEB SITE:
E-MAIL:
BAGHOUSE FILTRATION PRODUCTS
CONTROL OF PM2 5 EMISSIONS BY BAGHOUSE
FILTRATION PRODUCTS
5117 High Durability PPS Laminate Filtration Media
W. L. Gore & Associates, Inc.
101 Lewisville Rd.
Elkton, MD 21922
http: //www. gore. com
stims@wlgore .com
PHONE: 410-506-3348
FAX: 410-398-6624
The U.S. Environmental Protection Agency (EPA) created the Environmental Technology Verification
(ETV) Program to facilitate the deployment of innovative or improved environmental technologies
through performance verification and dissemination of information. The goal of the ETV Program is to
further environmental protection by accelerating the acceptance and use of improved and cost-effective
technologies. The ETV Program seeks to achieve this goal by providing high-quality, peer-reviewed data
on technology performance to those involved in the design, distribution, financing, permitting, purchase,
and use of environmental technologies.
The ETV Program works in partnership with recognized standards and testing organizations; stakeholder
groups, which consist of buyers, vendor organizations, permitters, and other interested parties; and with
the full participation of individual technology developers. The program evaluates the performance of
innovative technologies by developing test plans that are responsive to the needs of stakeholders,
conducting field or laboratory tests (as appropriate), collecting and analyzing data, and preparing peer-
reviewed reports. All evaluations are conducted in accordance with rigorous quality assurance (QA)
protocols to ensure that data of known and adequate quality are generated and that the results are
defensible.
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The Air Pollution Control Technology Center (APCT Center) is operated by RTI International* (RTI), in
cooperation with EPA's National Risk Management Research Laboratory (NRMRL). The APCT Center
evaluates the performance of baghouse filtration products (BFPs) used primarily to control PM25
emissions (i.e., particles 2.5 um and smaller in aerodynamic diameter). This verification statement
summarizes the test results for W. L. Gore & Associates, Inc.'s 5117 High Durability PPS Laminate
filtration media.
VERIFICATION TEST DESCRIPTION
All tests were performed in accordance with the APCT Center Generic Verification Protocol for
Baghouse Filtration Products, available at http://www.epa.gov/etv/pubs/05_vp_bfp.pdf The protocol is
based on and describes modifications to the equipment and procedures described in Verein Deutscher
Ingenieure (VDI) 3926, Part 2, Testing of Filter Media for Cleanable Filters under Operational
Conditions, December 1994. The VDI document is available from Beuth Verlag GmbH, 10772 Berlin,
Germany. The protocol also includes requirements for quality management and QA, procedures for
product selection, auditing of the test laboratories, and the test reporting format.
Outlet particle concentrations from a test fabric were measured with an impactor equipped with
appropriate substrates to filter and measure PM2 5 within the dust flow. Outlet particle concentrations were
determined by weighing the mass increase of dust collected in each impactor filter stage and dividing by
the gas volumetric flow through the impactor.
Particle size was measured while injecting the test dust into the air upstream of the baghouse filter
sample. The test dust was dispersed into the flow using a brush-type dust feeder. The particle size
distributions in the air were determined both upstream and downstream of the test filter fabric to provide
accurate results for penetration of PM2 5 through the test filter. All tests were performed using a constant
18.4 ± 3.6 g/dscm (8.0 ± 1.6 gr/dscf) loading rate, a 120 ± 6.0 m/h (6.6 ± 0.3 fpm) filtration velocity
[identical to gas-to-cloth ratio (G/C**)], and aluminum oxide test dust with a measured mass mean
aerodynamic diameter maximum of 1.5 um (average of three impactor runs). All BFPs are tested in their
initial (i.e., clean) condition.
Each of the three test runs consisted of the following segments:
Conditioning period—10,000 rapid-pulse cleaning cycles
Recovery period—30 normal-pulse cleaning cycles
Performance test period—6-hour filter fabric test period with impactor.
VERIFIED TECHNOLOGY DESCRIPTION
Baghouses are air pollution control devices used to control particulate emissions from stationary sources
and are among the technologies evaluated by the APCT Center. Baghouses and their accompanying filter
media have long been one of the leading particulate control techniques for industrial sources. Increasing
emphasis on higher removal efficiencies has helped the baghouse to be continually more competitive
when compared to the other generic PM control devices to the point where the baghouse is now the
control option of choice for most industrial applications. The development of new and improved filter
media has further enhanced baghouse capability to control fine PM over an expanded range of industrial
applications.
* RTI International is a trade name of Research Triangle Institute.
"Filtration velocity and gas-to-cloth ratio are used interchangeably and are defined as the gas flow rate divided by
the surface area of the cloth.
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W. L. Gore & Associates, Inc. provided the following information about their filter media product. The
W. L. Gore & Associates, Inc. 5117 High Durability PPS Laminate is a 16 ounces per square yard
(oz/yd2) polyphenylene sulfide (PPS) felt laminated with GORE™ Membrane (expanded
polytetrafluoroethylene, ePTFE). Figure 1 is a photograph of the fabric. Sample material was received as
nine 46 x 91 cm (18 x 36 in.) swatches marked with the manufacturer's model number, year and month of
manufacture, and cake side (the upstream side of the fabric, which is exposed to the particle-laden air on
which the filter cake builds up). Three of the swatches were selected at random for preparing three
circular test specimens 150 mm (5.9 in.) in diameter.
W.L. Gore
PC#5117
ePTFE Membrane PPS Felt
Figure 1. Photograph of W. L. Gore & Associates, Inc.'s 5117 High Durability
PPS Laminate filtration media
VERIFICATION OF PERFORMANCE
Verification testing of the W. L. Gore & Associates, Inc.'s 5117 High Durability PPS Laminate filtration
media was performed during the period of March 28 - April 4, 2012, for standard test conditions at the
test facility of ETS Incorporated, 1401 Municipal Road NW, Roanoke, VA 24012. Test conditions are
listed in Table 1. The overall test results summarized in Table 2 represent the averages of three
individual tests.
The APCT Center quality manager has reviewed the test results and the quality control (QC) data and has
concluded that the data quality objectives given in the generic verification protocol and test/QA plan have
been attained.
This verification statement addresses five aspects of filter fabric performance: filter outlet PM2s
concentration, filter outlet total mass concentration, pressure drop, filtration cycle time, and mass gain on
the filter fabric. Users may wish to consider other performance parameters, such as temperature, service
life, and cost when selecting a filter fabric for their application.
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Table 1. Test Conditions for Baghouse Filtration Products
Brand/Model: W. L. Gore & Associates, Inc.'s 5117 High Durability
PPS Laminate Filtration Media
Test Parameter
Dust concentration
Filtration velocity (G/C)
Pressure loss before cleaning
Tank pressure
Valve opening time
Air temperature
Relative humidity
Total raw gas stream flow rate
Sample gas stream flow rate
Number of cleaning cycles
• During conditioning period
• During recovery period
Performance test duration
Value
18.4 ± 3.6 g/dscm (8.0 ± 1 .6 gr/dscf)
120±6m/h(6.6±0.3fpm)
1, 000 ±12 Pa (4 ±0.05 in. w.g.)
0.5 ± 0.03 MPa (75 ± 5 psi)
50 ± 5 ms
25 ± 2 °C (77 ± 4 °F)
50 ± 1 0%
5.8 ± 0.3 m3/h (3.4 ± 0.2 cfm)
1.13 ± 0.06 m3/h (0.67 ± 0.03 cfm)
—
10,000 cycles
30 cycles
6h±1 s
Beginning of table description. Table 1 is titled Test Conditions for Baghouse Filtration Products; the
Brand/Model is listed as W. L. Gore & Associates, Inc.'s 5117 High Durability PPS Laminate Filtration
Media. The table describes the test conditions that are specified in the QA/QC requirements for the test;
all conditions were achieved for this test. The table lists the test parameters in one column and their
values in the next column. The test parameters include such items as the dust concentration, filtration
velocity, flow rates, air temperature and humidity, and the number of cleaning cycles during the test. End
of table description.
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Table 2. Baghouse Filtration Product Three-Run Average Test Results
forW. L. Gore & Associates, Inc.'s 5117 High Durability PPS Laminate Filtration Media
Verification Parameter
Outlet particle concentration at standard conditions3
PM2 5, g/dscm
(gr/dscf)
Total mass, g/dscmb
(gr/dscf)
Average residual pressure drop (A P), cm w.g. (in. w.g.)
Initial residual A P, cm w.g. (in. w.g.)
Residual A P increase, cm w.g. (in. w.g.)
Filtration cycle time, s
Mass gain of test sample filter, g (gr)
Number of cleaning cycles
At Verification Test
Conditions
<0.0000167C
(<0.0000073)
<0.0000167C
(<0.0000073)
2.09 (0.82)
2.06 (0.81)
0.07 (0.03)
255
0.13(1.95)
84
a Standard conditions: 101.3 kPa (14.7 psia) and 20 °C (68 °F). One or more of the impactor substrate weight
changes for these results were near the reproducibility of the balance.
b Total mass includes the mass of PM2.5 and larger particles that passed through the fabric.
c The measured value was determined to be below the detection limit of 0.0000167 grams per cubic meter. The
detection limit is for a 6-hour test and based on VDI 3926.
Beginning of table description. Table 2 is titled Baghouse Filtration Product Three-Run Average Test
Results for W. L. Gore & Associates, Inc.'s 5117 High Durability PPS Laminate Filtration Media. The
table lists the verified test results for this product. The table lists the verification parameters in one
column and their values at the verification test conditions in the next column. The verification parameters
listed include the outlet particle concentration, the pressure drop characteristics, the filtration cycle time,
the mass gain of the test sample, and number of cycles during the test. End of table description.
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In accordance with the generic verification protocol, this verification statement is applicable to filter
media manufactured between the signature date of the verification statement and 3 years thereafter.
signed by Cynthia Sonich-Mullin
V27/2012 sisned by Jason Hill
Date
Cynthia Sonich-Mullin
Director
National Risk Management Research Laboratory
Office of Research and Development
United States Environmental Protection Agency
6/27/2012
Date
Jason Hill
Director
Air Pollution Control Technology Center
RTI International
NOTICE: ETV verifications are based on an evaluation of technology performance under specific,
predetermined criteria and the appropriate quality assurance procedures. EPA and RTI make no express
or implied warranties as to the performance of the technology and do not certify that a technology will
always operate as verified. The end user is solely responsible for complying with any and all applicable
federal, state, and local requirements. Mention of commercial product names does not imply
endorsement.
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
Notice
This document was prepared by RTI International (RTI) and its subcontractor ETS Incorporated (ETS)
with partial funding from Cooperative Agreement No. CR 83416901-0 with the U.S. Environmental
Protection Agency (EPA). The document has been subjected to RTI/EPA's peer and administrative
reviews and has been approved for publication. Mention of corporation names, trade names, or
commercial products does not constitute endorsement or recommendation for use of specific products.
RTI International is a trade name of Research Triangle Institute.
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
Foreword
The Environmental Technology Verification (ETV) Program, established by the U.S. Environmental
Protection Agency (EPA), is designed to accelerate the development and commercialization of new or
improved technologies through third-party verification and reporting of performance. The goal of the
ETV Program is to verify the performance of commercially ready environmental technologies through the
evaluation of objective and quality-assured data in order to provide potential purchasers and permitters an
independent, credible assessment of the technology that they are buying or permitting.
The Air Pollution Control Technology Center (APCT Center) is part of the EPA's ETV Program and is
operated as a partnership between RTI International (RTI) and EPA. The APCT Center verifies the
performance of commercially ready air pollution control technologies. Verification tests use approved
protocols, and verified performance is reported in verification statements signed by EPA and RTI
officials. RTI contracts with ETS Incorporated (ETS) to perform verification tests on baghouse filtration
products, including filter media.
Baghouses are air pollution control devices used to control particulate emissions from stationary sources
and are among the technologies evaluated by the APCT Center. Baghouses and their accompanying filter
media have long been one of the leading particulate control techniques for industrial sources. Increasing
emphasis on higher removal efficiencies has helped the baghouse to be continually more competitive
when compared to the other generic PM control devices to the point where the baghouse is now the
control option of choice for most industrial applications. The development of new and improved filter
media has further enhanced baghouse capability to control fine PM over an expanded range of industrial
applications. The APCT Center developed (and EPA approved) the Generic Verification Protocol for
Baghouse Filtration Products to provide guidance on these verification tests.
The following report reviews the performance of W. L. Gore & Associates, Inc.'s 5117 High Durability
PPS Laminate filtration media. ETV testing of this technology was conducted during March - April 2012
at ETS. All testing was performed in accordance with an approved test/quality assurance (QA) plan that
implements the requirements of the generic verification protocol at the test laboratory.
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
Availability of Verification Statement and Report
Copies of this verification report are available from the following:
RTI International
Discovery & Analytical Sciences
P.O. Box 12194
Research Triangle Park, NC 27709-2194
U.S. Environmental Protection Agency
Air Pollution Prevention and Control Division (E343-02)
109 T. W. Alexander Drive
Research Triangle Park, NC 27711
Web Site: http://www.epa.gov/etv/vt-apc.html (electronic copies)
in
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
Table of Contents
Page
Notice i
Foreword ii
Availability of Verification Statement and Report iii
List of Figures v
List of Tables v
List of Abbreviations and Acronyms vi
Acknowledgments viii
1.0 Introduction 1
2.0 Verification Test Description 2
2.1 Description of the Test Rig and Methodology 2
2.2 Selection of Filtration Sample for Testing 4
2.3 Control Tests 4
2.4 Analysis 5
3.0 Description of Filter Fabric 7
4.0 Verification of Performance 8
4.1 Quality Assurance 8
4.2 Results 8
4.3 Limitations and Applications 9
5.0 References 10
IV
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
List of Figures
Page
Figure 1. Diagram of filtration efficiency media analyzer test apparatus 3
Figure 2. Photograph of W. L. Gore & Associates, Inc.'s 5117 High Durability PPS Laminate filtration
media 7
List of Tables
Table 1. Summary of Control Test Results 5
Table 2. Summary of Verification Results for W. L. Gore & Associates, Inc.'s 5117 High Durability PPS
Laminate Filtration Media 9
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Environmental Technology Verification Report
W. L. Gore & Associates, Inc., 5117
List of Abbreviations and Acronyms
APCT Center Air Pollution Control Technology Center
BFP baghouse filtration product
cfm cubic feet per minute
cm centimeter(s)
cm w.g. centimeter(s) of water gauge
dia. diameter
AP pressure drop
dscmh dry standard cubic meter(s) per hour
EPA U.S. Environmental Protection Agency
ePTFE expanded polytetrafluoroethylene
ETS ETS Incorporated
ETV Environmental Technology Verification
FEMA filtration efficiency media analyzer
fprn feet per minute
g gram(s)
g/dscm gram(s) per dry standard cubic meter
g/m3 gram(s) per cubic meter
G/C gas-to-cloth ratio (filtration velocity)
gr grain(s)
gr/dscf grain(s) per dry standard cubic foot
GVP generic verification protocol
h hour(s)
in. inch(es)
in. w.g. inch(es) of water gauge
kPa kilopascal(s)
VI
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
m meter(s)
m/h meter(s) per hour
m3/h cubic meter(s) per hour
mbar millibar(s)
min. minute(s)
mm millimeter(s)
MPa megapascal(s)
ms millisecond(s)
oz/yd2 ounce(s) per square yard
Pa pascal(s)
PM particulate matter
PM2 5 particulate matter 2.5 micrometers in aerodynamic diameter or smaller
PPS polyphenylene sulfide
psi pound(s) per square inch
psia pound(s) per square inch absolute
QA quality assurance
QC quality control
RTI RTI International
s second(s)
t time
VDI Verein Deutscher Ingenieure
(im micrometer(s)
°C degree(s) Celsius
°F degree(s) Fahrenheit
°R degree(s) Rankine
vn
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
Acknowledgments
The authors acknowledge the support of all those who helped plan and conduct the verification activities.
In particular, we would like to thank Michael Kosusko, U.S. Environmental Protection Agency's (EPA's)
Project Officer, and Bob Wright, EPA's Quality Manager, who both work as part of EPA's National Risk
Management Research Laboratory in Research Triangle Park, NC. Finally, we would like to acknowledge
the assistance and participation of W. L. Gore & Associates, Inc. personnel, who supported the test effort.
For more information on W. L. Gore & Associates, Inc.'s 5117 High Durability PPS Laminate, contact
the following:
Mr. Scot Tims
W. L. Gore & Associates, Inc.
lOlLewisvilleRd.
Elkton,MD21922
410-506-3348
stims@wlgore.com
For more information on verification testing of baghouse filtration products, contact the following:
Mr. Jason Hill
RTI International
P.O. Box 12194
Research Triangle Park, NC 27709-2194
919-541-7443
APCTVC@,rti.org
Vlll
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
1.0 INTRODUCTION
This report reviews the pressure drop (AP) and filtration performance of W. L. Gore & Associates, Inc.'s
5117 High Durability PPS Laminate filtration media. Environmental Technology Verification (ETV)
testing of this technology/product was conducted during a series of tests in March - April 2012 by ETS
Incorporated (ETS), under contract with the Air Pollution Control Technology Center (APCT Center).
The objective of the APCT Center and the ETV Program is to verify, with high data quality, the
performance of air pollution control technologies. Control of fine-particle emissions from various
industrial and electric utility sources employing baghouse control technology is within the scope of the
APCT Center. An APCT Center program area was designed by RTI International (RTI) and a technical
panel of experts to evaluate the performance of particulate filters for fine-particle (i.e., PM25) emission
control. Based on the activities of this technical panel, the Generic Verification Protocol for Baghouse
Filtration Products1 was developed. This protocol was chosen as the best guide to verify the filtration
performance of baghouse filtration products (BFPs). The specific test/quality assurance (QA) plan for the
ETV test of the technology was developed and approved in May 2000, followed by an approved update in
February 20062. The goal of the test was to measure filtration performance of both PM2s and total
particulate matter (PM), as well as the AP characteristics of the W. L. Gore & Associates, Inc. technology
identified above.
Section 2 of this report documents the procedures used for the test and the conditions over which the test
was conducted. A description of W. L. Gore & Associates, Inc.'s 5117 High Durability PPS Laminate
filtration media is presented in Section 3. The results of the test are summarized and discussed in Section
4, and references are presented in Section 5.
This report contains summary information and data from the test and the verification statement. Complete
documentation of the test results is provided in a separate data package report and an audit of data quality
report. These reports include the raw test data from product testing and supplemental testing as well as
QA and quality control (QC) activities and results. Complete documentation of QA/QC activities and
results, raw test data, and equipment calibration results are retained in ETS's files for 7 years.
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
2.0 VERIFICATION TEST DESCRIPTION
The BFPs were tested in accordance with the APCT Center Generic Verification Protocol for Baghouse
Filtration Products1 and the Test/QA Plan for the Verification Testing of Baghouse Filtration Products2
These documents incorporate all the requirements for quality management, QA, procedures for product
selection, auditing of the test laboratories, and reporting format. The Generic Verification Protocol (GVP)
describes the overall procedures used for verification testing and defines the data quality objectives. The
protocol is based on and describes modifications to the equipment and procedures described in Verein
Deutscher Ingenieure (VDI) 3926, Part 2, Testing of Filter Media for Cleanable Filters under
Operational Conditions, December 1994.3 The values for inlet dust concentration, raw gas flow rate, and
filtration velocity used for current verification testing have been revised in consultation with the technical
panel since posting of the GVP. These revisions are documented in Section 4.1. The test/QA plan details
how the test laboratory at ETS implemented and met the requirements of the GVP.
2.1 Description of the Test Rig and Methodology
The tests were conducted in ETS's filtration efficiency media analyzer (FEMA) test apparatus (Figure 1).
The test apparatus is based on the VDI 3926 Type 1 vertical duct design. The test apparatus consists of a
brush-type dust feeder that disperses test dust into a vertical rectangular duct (raw-gas channel). The dust
feed rate is continuously measured and recorded via an electronic scale located beneath the dust feed
mechanism. The scale has a continuous readout with a resolution of 10 g. A radioactive polonium-210
alpha source is used to neutralize the dust electrically before its entry into the raw-gas channel. An optical
photo sensor monitors the concentration of dust and ensures that the flow is stable for the entire duration
of the test. The optical photo sensor does not measure absolute concentration, and is, therefore, not the
primary concentration measurement for the test. A portion of the gas flow is extracted from the raw-gas
channel through the test filter, which is mounted vertically at the entrance to a horizontal duct (clean-gas
channel). The clean-gas channel flow is separated into two gas streams, a sample stream and a bypass
stream. An aerodynamic "Y" is used for this purpose. The aerodynamic "Y" is designed for isokinetic
separation of the clean gas with 40% of the clean gas entering the sample-gas channel without change in
gas velocity. The sample-gas channel contains an Andersen impactor for particle separation and
measurement. The bypass channel contains an absolute filter. The flow within the two segments of the
"Y" is continuously monitored and maintained at selected rates by adjustable valves. Two vacuum pumps
maintain air flow through the raw-gas and clean-gas channels. The flow rates, and thus the gas-to-cloth
ratio (G/C) through the test filter, are kept constant and measured using mass flow controllers. A pressure
transducer is used to measure the average residual AP of the filter sample. The pressure transducer
measures the differential pressure across the filter samples every 3 seconds; the residual AP measurements
are those taken 3 seconds after the cleaning pulse. The AP measurements are then averaged, as described
in Appendix C, Section 4.4.1 of the GVP.1 High-efficiency filters are installed upstream of the flow
controllers and pumps to prevent contamination or damage caused by the dust. The cleaning system
consists of a compressed-air tank set at 0.5 MPa (75 psi), a quick-action diaphragm valve, and a blow
tube [25.4 mm (1.0 in.) dia.] with a nozzle [3 mm (0.12 in.) dia.] facing the downstream side of the test
filter.
Mean outlet particle concentration is determined when a portion of the gas flow is extracted from the raw-
gas channel through the test filter, which is mounted vertically at the entrance to a horizontal duct (clean-
gas channel). The clean-gas flow is separated using an aerodynamic 'Y"" so that a representative sample
of the clean gas flows through an Andersen impactor that determines the outlet particle concentration.
Outlet particle concentrations were determined by weighing the mass increase of dust collected in each
impactor filter stage and dividing by the gas volumetric flow through the impactor.
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Environmental Technology Verification Report
W. L. Gore & Associates, Inc., 5117
The particle size was measured while a fine dust was injected into the air stream upstream of the filter
fabric sample. The particle size distributions in the air were determined both upstream and downstream
of the test filter fabric to provide accurate results for penetration through the test filter of PM25.
DUST FEED FROM EXTERNAL HOPPER
DUST CHARGE NEUTRALIZER
RECTANGULAR CHANNEL
111 x 292 mm (4-3/8x11-1/2")
PHOTOMETER
FILTER FIXTURE AND TEST FILTER
CYLINDRICAL EXTRACTION TUBE
CLEAN-GAS SAMPLE PORT
RAW-GAS SAMPLE PORT
CLEANING SYSTEM
BACKUP
FILTER
MASS FLOW
CONTROLLER
ABSOLUTE FILTER AND
ANDERSENIMPACTOR
ADJUSTABLE
VALVES
CALIBRATED
ORIFICE
BLOW TUBE
DIRTY AIR
FILTER
CLEAN AIR PUMP
MASS FLOW
CONTROLLER
DIRTY AIR
PUMP
DUST
CONTAINER
Figure 1. Diagram of filtration efficiency media analyzer test apparatus.
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
The following series of tests was performed on three separate, randomly selected filter fabric samples:
• Conditioning period
• Recovery period
• Performance test period.
To simulate long-term operation, the test filter was first subjected to a conditioning period, which consists
of 10,000 rapid-pulse cleaning cycles under continuous dust loading. During this period, the time between
cleaning pulses was maintained at 3 seconds. No filter performance parameters are measured in this
period.
The conditioning period is immediately followed by a recovery period, which allows the test filter fabric
to recover from rapid pulsing. The recovery period consists of 30 normal filtration cycles under
continuous and constant dust loading. During a normal filtration cycle, the dust cake is allowed to form
on the test filter until a differential pressure of 1,000 Pa (4.0 in. w.g.) is reached. At this point, the test
filter is cleaned by a pulse of compressed air from the clean-gas side of the fabric. The next filtration
cycle begins immediately after the cleaning is complete.
Performance testing occurred for a 6-hour period immediately following the recovery period (a
cumulative total of 10,030 filtration cycles after the test filter had been installed in the test apparatus).
During the performance test period, normal filtration cycles are maintained and, as in the case of the
conditioning and recovery periods, the test filter is subjected to continuous and constant dust loading.
The filtration velocity (G/C) and inlet dust concentrations were maintained at 120 ± 6 m/h (6.6 ± 0.3 fpm)
and 18.4 ± 3.6 g/dscm (8.0 ±1.6 gr/dscf), respectively, throughout all phases of the test.
2.2 Selection of Filtration Sample for Testing
Filter fabric samples of 5117 High Durability PPS Laminate filtration media were supplied to ETS
directly from the manufacturer (W. L. Gore & Associates, Inc.), with a letter signed by John F. McMillan,
Business Leader, W. L. Gore & Associates, Inc., attesting that the filter media were selected at random in
an unbiased manner from commercial-grade media and were not treated differently in any manner from
the media provided to customers. The manufacturer supplied the test laboratory with nine 46x91 cm
(18 x 36 in.) filter samples. The test laboratory randomly selected three samples and prepared them for
testing by cutting one test specimen of 150 mm (5.9 in.) diameter from each selected sample for insertion
in the test rig sample holder. The sample holder has an opening 140 mm (5.5 in.) in diameter, which is the
dimension used to calculate the face area of the tested specimen.
2.3 Control Tests
Two types of control tests were performed during the verification test series. The first was a dust
characterization, which is performed monthly. The reference dust used during the verification tests was
Pural NF aluminum oxide dust. The Pural NF dust was oven dried for 2 hours and sealed in an airtight
container prior to its insertion into the FEMA apparatus. The criteria for the dust characterization test are
a maximum mass mean diameter of 1.5 ± 1.0 urn and a concentration between 40% and 90% of particles
less than 2.5 (im. These criteria must be met in order to continue the verification test series.
The second control test, the reference value test, is performed quarterly using the reference fabric and the
FEMA apparatus. The reference value test determines the weight gain of the reference fabric, as well as
the maximum AP (final residual pressure drop). The results of the test verified that the FEMA apparatus
was operating consistently within the required parameters. The average fabric maximum AP (average of
the repeated measurements of final residual pressure drop conducted during the quarter applicable to this
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Environmental Technology Verification Report
W. L. Gore & Associates, Inc., 5117
test) in a reference value test must be 0.60 cm w.g. ± 40%, and the fabric weight gain average must be
1.12 g ± 40%. Three reference value control test runs were conducted. The results of the control tests are
summarized in Table 1.
Table 1. Summary of Control Test Results
—
Mass mean diameter, urn
% Less than 2.5 urn
Weight gain, g
Maximum pressure drop, cm w.g.
Requirement
1.5± 1.0
40%-90%
1.12 ±40%
0.60 ± 40%
Measured Value
2.33
52.79%
0.71
0.51
Criteria Met
Yes
Yes
Yes
Yes
Beginning of table description. Table 1 is titled Summary of Control Test Results. The table lists the
results of measurements meant to characterize the operation of the test apparatus. The mass mean
diameter of the challenge aerosol, the percent less than 2.5 micrometers in diameter, the weight gain of a
reference fabric and the maximum pressure drop of the reference fabric were measured. In columns, the
table lists the QA/QC requirements, the values measured during the control tests, and whether or not the
criteria were met. For this test, all criteria were met. End of table description.
2.4 Analysis
The equations used for verification analysis are described below.
Af
Cds
C2.5ds
dia.
Fa
Fs
G/C
Mt
M2.5
N
"avg
P,
PS
Qa
Qds
Q2.5dS
Qst
t
to
Ts
Exposed area of sample filter, m2
Dry standard outlet particulate concentration of total mass, g/dscm
Dry standard outlet particulate concentration of PM2 5, g/dscm
Diameter of exposed area of sample filter, m
Dust feed concentration corrected for actual conditions, g/m3
Dust feed concentration corrected for standard conditions, g/dscm
Gas-to-cloth ratio, m/h
Total mass gain from Andersen impactor, g
Total mass gain of particles equal to or less than 2.5 urn diameter from Andersen
impactor, g. This value may need to be linearly interpolated from test data.
Number of filtration cycles in a given performance test period
Average residual AP, cm w.g.
Residual AP for /th filtration cycle, cm w.g.
Absolute gas pressure as measured in the raw-gas channel, mbar
Actual gas flow rate, m3/h
Dry standard gas flow rate, dscmh
Dry standard gas flow rate for 2.5 urn particles, dscmh
Standard gas flow rate for a specific averaging time, t, dscmh
Specified averaging time or sampling time, s
Average filtration cycle time, s
Raw-gas channel temperature, °F
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Environmental Technology Verification Report
W. L. Gore & Associates, Inc., 5117
Wf = Weight of dust in feed hopper following specified time, g. Because of vibrations causing
short-term fluctuations to the feed hopper, this value is measured as a 1-min. average.
w; = Weight of dust in feed hopper at the beginning of the specified time, g. Due to vibrations
causing short-term fluctuations to the feed hopper, this value is measured as a 1-min.
average.
Conversion factors and standard values used in the equations are listed below.
460 = 0 °F, in °R
1,013 = Standard atmospheric pressure, mbar
528 = Standard temperature, °R
Area of Sample Fabric, Af
Af =
Actual Gas Flow Rate, Qa
(7;+460)* 1013
Qa=Qds*
P *528
Gas-to-Cloth Ratio, G/C
G = QL
C Af
Standard Dust Feed Concentration, Fs, for a specified time, t
= (w,-wf)
s~ fe**0
Actual Raw Gas Dust Concentration, Fa
fc+ 460)* 1013
=Ft
Dry Standard Clean Gas Particulate Concentration, Total Mass, Cds
Mt
Q**t*\\-
%H2O
100 ,
Dry Standard Clean Gas Particulate Concentration, PM2 5, C2 5d
100
Filtration Cycle Time, tc
Average Residual Pressure Drop, Pa
p =^
"' N
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Environmental Technology Verification Report
W. L. Gore & Associates, Inc., 5117
3.0 DESCRIPTION OF FILTER FABRIC
The W. L. Gore & Associates, Inc. 5117 High Durability PPS Laminate is a 16 ounces per square yard
(oz/yd2) polyphenylene sulfide (PPS) felt laminated with GORE™ Membrane (expanded
polytetrafluoroethylene, ePTFE). Figure 2 is a photograph of the fabric. Sample material was received as
nine 46 x 91 cm (18 x 36 in.) swatches marked with the manufacturer's model number, year and month of
manufacture, and cake side (the upstream side of the fabric, which is exposed to the particle-laden air, on
which the filter cake builds up). Three of the swatches were selected at random for preparing three
circular test specimens 150 mm (5.9 in.) in diameter.
W.L. Gore
PC#5117
ePTFE Membrane PPS Felt
Figure 2. Photograph of W. L. Gore & Associates, Inc.'s 5117 High Durability
PPS Laminate filtration media.
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
4.0 VERIFICATION OF PERFORMANCE
4.1 Quality Assurance
The verification tests were conducted in accordance with an approved test/QA plan.2 The EPA quality
manager conducted an independent assessment of the test laboratory in June 2005 and found that the test
laboratory was equipped and operated as specified in the test/QA plan.
The ETS QA officer and the APCT Center's QA staff have reviewed the results of this test and have
found that the results meet the overall data quality objectives as stated in the test/QA plan. It should be
noted that, because of the highly efficient nature of the filter medium being tested, one or more of the
impactor substrate weighings for these results were below the reproducibility of the balance. The relative
percent error in the post-filter weighing measurements cannot be computed because some of the values
were near zero. As a result of this occurrence, the tests do not meet the data quality objectives (DQOs)
stated in the test/QA plan for mass gain associated with outlet concentrations. However, as stated in the
test protocol, "for highly efficient fabrics, the mass gains stated for these quality objectives may not be
achieved in the specified test duration. For these tests it is acceptable for the indicated DQO not to be
met."
Data on calibration certificates for the flow meters, flow transducers, weights, low- and high-resolution
balances, thermometer, and humidity logger are maintained at ETS in a separate data package.
Deviations from the test plan include organizational personnel changes.
The ETS QA officer and the APCT Center's QA staff have also reviewed the results of the control tests,
which are summarized in Section 2.3, Table 1. The dust characterization control test met the appropriate
requirements of the test/QA plan and verification protocol. The reference fabric tests met maximum AP
and weight gain requirements established for reference fabric performance in the GVP, indicating the
measurement system is operating in control.
4.2 Results
Table 2 summarizes the mean outlet particle concentration measurements for the verification test periods.
Measurements were conducted during the 6-hour performance test period. The performance test period
followed a 10,000-cycle conditioning period and a 30-cycle recovery period.
Table 2 summarizes the three verification tests that were performed under standard verification test
conditions. The average residual AP across each filter sample at the nominal 120 m/h (6.6 fpm) filtration
velocity [for a flow rate of 5.8 m3/h (3.4 cfin)] is also shown in Table 2. This AP ranged from 1.81 to 2.33
cm w.g. (0.71 to 0.92 in. w.g.) for the three filter samples tested. The residual AP increase ranged from
0.06 to 0.08 cm w.g. (0.02 to 0.03 in. w.g.) for the samples tested. All three standard condition
verification runs were used to compute the averages given in Table 2. The PM25 outlet particle
concentration average for the three runs is < 0.0000167 g/dscm. The total PM concentration average for
the three runs is < 0.0000167 g/dscm.
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Environmental Technology Verification Report
W. L. Gore & Associates, Inc., 5117
Table 2. Summary of Verification Results for W. L. Gore & Associates, Inc.'s 5117 High
Durability PPS Laminate Filtration Media
Test Run Number
PM2.5 (g/dscm)b
Total PM (g/dscm)
Average residual AP (cm w.g.)
Initial residual AP (cm w.g.)
Residual AP increase (cm w.g.)
Mass gain of sample filter (g)
Average filtration cycle time (s)
Number of cleaning cycles
6V1-R1
<0.0000167C
<0.0000167C
1.81
1.78
0.08
0.14
270
79
6V1-R2
<0.0000167
<0.0000167
2.13
2.11
0.06
0.10
243
88
6V1-R3
<0.0000167
<0.0000167
2.33
2.30
0.06
0.14
252
85
Averagea
<0.0000167
<0.0000167
2.09
2.06
0.07
0.13
255
84
a All three verification runs were used to compute averages.
b One or more of the impactor substrate weight changes for these results were near the reproducibility limit of the
balance.
c The measured value was determined to be below the detection limit of 0.0000167 grams per cubic meter. The
detection limit is for a six-hour test and based on VDI 3926.
Beginning of table description. Table 2 is titled Summary of Verification Results for W. L. Gore &
Associates, Inc.'s 5117 High Durability PPS Laminate Filtration Media. The table lists the verified test
results for the three replicate test runs and their averages. The table lists the particle concentrations
downstream of the sample filters, the pressure drop characteristics, the mass gain of the sample filter, the
average filtration cycle time, and the number of cleaning cycles during the test. In separate columns,
results for these parameters are listed for each of the three test runs and their averages. End of table
description.
4.3 Limitations and Applications
This verification report addresses two aspects of BFP performance: outlet particle concentration and AP.
Users may wish to consider other performance parameters, such as service life and cost, when selecting a
baghouse filtration fabric for their application.
In accordance with the GVP, the verification statement, which summarizes this test report, is applicable to
BFPs manufactured between the signature date of the verification statement and three years thereafter.
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Environmental Technology Verification Report W. L. Gore & Associates, Inc., 5117
5.0 REFERENCES
1. RTI International. 2001. Generic Verification Protocol for Baghouse Filtration Products, RTI
International, Research Triangle Park, NC, February. Available at
http://www.epa.gov/etv/pubs/05 vpbfp.pdf (accessed April 20, 2012).
2. ETS Incorporated and RTI International. 2006. Test/QA Plan for the Verification Testing of
Baghouse Filtration Products (Revision 2), ETS Incorporated, Roanoke, VA, and RTI
International, Research Triangle Park, NC, February. Available at
http://www.epa.gov/etv/pubs/600etv06095.pdf (accessed April 20, 2012).
3. Verein Deutscher Ingenieure (VDI) .1994. VDI 3 926, Part 2, Testing of Filter Media for
Cleanable Filters under Operational Conditions, December 1994. Available from Beuth Verlag
GmbH, 10772 Berlin, Germany.
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